The South African Astronomical Observatory (SAAO) is the national centre for optical and infrared astronomy in South Africa. It was established in 1972. The observatory is run by the

National Research Foundation of South Africa South Africa’s National Research Foundation (NRF) is the intermediary agency between the policies and strategies of the Government of South Africa and South Africa's research institutions. History It was established on 1 April 1999 as an ...

. The facility's function is to conduct research in

astronomy Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...

and

astrophysics Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline, James Keeler, said, astrophysics "seeks to ascertain the ...

. The primary telescopes are located in

Sutherland Sutherland () is a Counties of Scotland, historic county, registration county and lieutenancy areas of Scotland, lieutenancy area in the Scottish Highlands, Highlands of Scotland. The name dates from the Scandinavian Scotland, Viking era when t ...

, which is from

Observatory, Cape Town Observatory is a suburb in Cape Town, South Africa, colloquially known as Obs. Bordered by Mowbray to the south and Salt River to the northwest, the area is best known as a student neighbourhood associated with the nearby University of Cape T ...

, where the headquarters is located. The SAAO has links worldwide for scientific and technological collaboration. Instrumental contributions from the South African Astronomical Observatory include the development of a spherical aberration corrector and the

Southern African Large Telescope The Southern African Large Telescope (SALT) is a 9.2-metre optical telescope designed mainly for spectroscopy. It consists of 91 hexagonal mirror segments each with a 1-metre inscribed diameter, resulting in a total hexagonal mirror of 11.1 by 9 ...

(SALT). The

Noon Gun The Noon Gun has been a historic time signal in Cape Town, South Africa, since 1806. It consists of a pair of black powder Dutch naval guns, fired alternatingly with one serving as a backup. The guns are situated on Signal Hill, close to th ...

on Cape Town's Signal Hill is fired remotely by a time signal from the Observatory.

History

The history of the SAAO began when the Royal Observatory at the Cape of Good Hope was founded in 1820, the first scientific institution in Africa. Construction of the main buildings was completed in 1829 at a cost of £30,000 (equivalent to £ in ). The post of ''His/Her Majesty's astronomer at the Cape of Good Hope'' was awarded the

Royal Medal The Royal Medal, also known as The Queen's Medal and The King's Medal (depending on the gender of the monarch at the time of the award), is a silver-gilt medal, of which three are awarded each year by the Royal Society. Two are given for "the mo ...

on two occasions; the first to

Thomas Maclear Thomas Maclear (17 March 1794 – 14 July 1879) was an Ireland, Irish-born Cape Colony astronomer who became Her Majesty's astronomer at the Cape of Good Hope. Early life Born on 17 March 1794, in Newtownstewart, the eldest son of Rev. James ...

in 1869 for measurement of an

arc of the meridian In geodesy and navigation, a meridian arc is the curve between two points near the Earth's surface having the same longitude. The term may refer either to a segment of the meridian, or to its length. Both the practical determination of meridian ...

at the Cape of Good Hope and the second to David Gill in 1903 for researches in solar and stellar parallax, and his energetic direction of the Royal Observatory at the Cape of Good Hope. The

Republic Observatory Union Observatory, also known as Transvaal Observatory, Republic Observatory and Johannesburg Observatory (IAU code#078, 078), is a defunct astronomical observatory in Johannesburg, South Africa that operated from 1903 to 1971. It is located on O ...

, Johannesburg, was merged with the much older Royal Observatory, Cape of Good Hope in January 1972 to form the South African Astronomical Observatory. In 1974 the

Radcliffe Observatory Radcliffe Observatory was the astronomical observatory of the University of Oxford from 1773 until 1934, when the Radcliffe Trustees sold it and built a new observatory in Pretoria, South Africa. It is a Grade I listed building. Today, the buil ...

telescope was purchased by the CSIR and moved to Sutherland, where it recommenced work in 1976. SAAO was established in January 1972, as a result of a joint agreement by the

Council for Scientific and Industrial Research A council is a group of people who come together to consult, deliberate, or make decisions. A council may function as a legislature, especially at a town, city or county/shire level, but most legislative bodies at the state/provincial or nati ...

(CSIR) of South Africa and

Science and Engineering Research Council The Science and Engineering Research Council (SERC) and its predecessor the Science Research Council (SRC) were the UK agencies in charge of publicly funded scientific and engineering research activities, including astronomy, biotechnology and bi ...

(SERC) of United Kingdom. The headquarters are located on the grounds of the old Royal Observatory where the main building, offices, national library for astronomy and computer facilities are housed. Historic telescopes are also found at the headquarters in a number of domes and a small museum that displays scientific instruments. The South African Astronomical Observatory is administered at present as a National Facility under management of the National Research Foundation (NRF), formerly the Foundation for Research Development (FRD). In 1974, when the Radcliffe Observatory in Pretoria closed, the Council for Scientific and Industrial Research (CSIR) purchased the 1.9-m Radcliffe Telescope and transported it to Sutherland.

Facilities

The observatory operates from the campus of the ''Royal Observatory, Cape of Good Hope'' that was established in 1820 in the suburb of

. The major observing facilities are, however, located near the town of Sutherland some from

Cape Town Cape Town is the legislature, legislative capital city, capital of South Africa. It is the country's oldest city and the seat of the Parliament of South Africa. Cape Town is the country's List of municipalities in South Africa, second-largest ...

. Sutherland was chosen because of its reliably clear and dark nights, but to ensure long term viability of the Karoo site astronomy instruments, the South African Parliament passed the Astronomy Geographic Advantage Act in 2007. The act gives the Minister of Science and Technology the authority to protect areas, through regulations, that are of strategic national importance for astronomy and related scientific endeavours.

Telescopes

0.50m telescope

This reflector was originally built for the

in 1967, but was moved to the Sutherland site in 1972. No longer in use. The 20" telescope was replaced with the Meerlicht telescope. The 20" telescope was relocated to the University of Freestate Boyden observatory and commissioned in ~2019

0.75m telescope

A Grubb Parsons reflector.

1.0m Telescope

This telescope was originally located at SAAO Head office in

, but has since moved to the Sutherland site. This telescope participates in the

PLANET A planet is a large, Hydrostatic equilibrium, rounded Astronomical object, astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets b ...

network.

1.9m Telescope

The 1.9-m (74-inch) Radcliffe Telescope was commissioned for the

Pretoria Pretoria ( ; ) is the Capital of South Africa, administrative capital of South Africa, serving as the seat of the Executive (government), executive branch of government, and as the host to all foreign embassies to the country. Pretoria strad ...

where it was in use between 1948 and 1974. Following the closure of the Radcliffe Observatory it was moved to

where it became operational again in January 1976. Between 1951 and 2004 it was the largest telescope in South Africa. The telescope was manufactured by Sir Howard Grubb, Parsons and Co.

Alan Cousins Telescope (ACT)

This telescope was originally called the Automatic Photometric Telescope, but has been renamed the Alan Cousins Telescope in honour of

Alan William James Cousins Alan William James Cousins FRAS (8 August 1903 – 11 May 2001) was a South African astronomer. His career spanned 70 years during which time he concentrated on the measurement of variable stars, including the measurement of the two sinusoidal ...

BiSON

One of six telescopes in the

Birmingham Solar Oscillations Network The Birmingham Solar Oscillations Network (BiSON) consists of a network of six remote solar observatories monitoring low-degree Helioseismology, solar oscillation modes. It is operated by the High Resolution Optical Spectroscopy group of the Sch ...

Infrared Survey Facility (IRSF)

The IRSF is a reflector fitted with a 3 colour Infrared Imager. Originally built as part of the ''Magellanic Clouds A Thorough Study'' grant from the Japanese Ministry of Education, Culture, Sports, Science and Technology in 2000. Other studies the telescope participated in include: * The Indian

Department of Space The Department of Space (DoS) is an Indian government department responsible for administration of the Indian space programme. It manages several agencies and institutes related to space exploration and space technologies. The Indian space pr ...

used this telescope for the ''Near Infrared Survey of the Nuclear Regions of the Milky Way'' to improve on data from the

DENIS Denis may refer to: People * Saint Denis of Paris, 3rd-century Christian martyr and first bishop of Paris * Denis the Areopagite, Biblical figure * Denis, Bishop of Győr (13th century), Hungarian prelate * Denis, son of Ampud (died 1236), bar ...

and

2MASS The Two Micron All-Sky Survey, or 2MASS, was an astronomical survey of the whole sky in infrared light. It took place between 1997 and 2001, in two different locations: at the U.S. Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona, and ...

Astronomical survey An astronomical survey is a general celestial cartography, map or astrophotography, image of a region of the sky (or of the whole sky) that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of image ...

Las Cumbres Observatory Global Telescope Network

Three telescopes to form part of the LCOGT network were installed in early 2013.

MASTER

The MASTER-SAAO Telescope (obs. code: K95) is part of the ''Russian Mobile Astronomical System of Telescope-Robots''. It saw first light on 21 December 2014. It consists of two paired 0.4-m telescopes. In April 2015 it discovered the first

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

from South Africa in 35 years, C/2015 G2 (MASTER).

MONET

One of the two telescopes of the MOnitoring NEtwork of Telescopes Project is located at Sutherland. Its twin can be found at the

McDonald Observatory McDonald Observatory is an astronomical observatory located near unincorporated community of Fort Davis in Jeff Davis County, Texas, United States. The facility is located on Mount Locke in the Davis Mountains of West Texas, with additional faci ...

in Texas. The MONET telescopes are

Robotic telescope A robotic telescope is an astronomical telescope and detector system that makes observations without the intervention of a human. In astronomical disciplines, a telescope qualifies as robotic if it makes those observations without being operated ...

controllable via the Internet and was constructed by the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen (, commonly referred to as Georgia Augusta), is a Public university, public research university in the city of Göttingen, Lower Saxony, Germany. Founded in 1734 ...

. Remote Telescope Markup Language is used to control the telescopes remotely.

PRIME

PRime-focus Infrared Microlensing Experiments is a telescope located in Sutherland. PRIME achieved first light on October 8, 2022. Currently PRIME has a

near-infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those of ...

camera located in its prime focus with a 1.29 square degree field of view. The telescope is a collaboration between

Osaka University The , abbreviated as UOsaka or , is a List of national universities in Japan, national research university in Osaka, Japan. The university traces its roots back to Edo period, Edo-era institutions Tekijuku (1838) and Kaitokudō, Kaitokudo (1724), ...

University of Maryland The University of Maryland, College Park (University of Maryland, UMD, or simply Maryland) is a public land-grant research university in College Park, Maryland, United States. Founded in 1856, UMD is the flagship institution of the Univ ...

, South African Astronomical Observatory,

NASA Goddard Space Flight Center The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory located approximately northeast of Washington, D.C., in Greenbelt, Maryland, United States. Established on May 1, 1959, as NASA's first space flight center, GSFC ...

and Astro-Biology Center. The project's primary science objective is the study of exoplanets using gravitational microlensing.

Project Solaris

Solaris-1 i Solaris-2 podczas nocnych obserwacji w SAAO

Two telescopes forming part of Project Solaris is located at the Sutherland site. Solaris-1 and Solaris-2 are both 0.5m f/15

Ritchey–Chrétien telescope A Ritchey–Chrétien telescope (RCT or simply RC) is a specialized variant of the Cassegrain telescope that has a hyperboloid, hyperbolic primary mirror and a hyperbolic secondary mirror designed to eliminate off-axis optical errors (Coma (optic ...

. The aims of Project Solaris is to detect circumbinary planets around

eclipsing binary A binary star or binary star system is a Star system, system of two stars that are gravity, gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved ...

stars and to characterise these binaries to improve stellar models. SA large telescope

Southern African Large Telescope (SALT)

:''Observatory Code: B31'' :''Observations
(Near Earth Objects)
' SALT was inaugurated in November 2005. It is the largest single optical telescope in the Southern Hemisphere, with a hexagonal mirror array 11 meters across. SALT shares similarities with the Hobby-Eberly Telescope (HET) in Texas. The Southern African Large Telescope gathers twenty-five times as much light as any other existing African Telescope. With this larger mirror array, SALT can record distant

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

galaxies A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar Sys ...

and

quasars A quasar ( ) is an extremely Luminosity, luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object, abbreviated QSO. The emission from an AGN is powered by accretion onto a supermassive black hole with a mass rangi ...

SuperWASP-South

The Wide Angle Search for Planets consists of two

robotic telescope A robotic telescope is an astronomical telescope and detector system that makes observations without the intervention of a human. In astronomical disciplines, a telescope qualifies as robotic if it makes those observations without being operated ...

s, the one located at SAAO

and the other at

Roque de los Muchachos Observatory Roque de los Muchachos Observatory (, ORM) is an astronomical observatory located in the municipality of Garafía on the island of La Palma in the Canary Islands, Spain. The observatory site is operated by the Instituto de Astrofísica de Can ...

on the island of

La Palma La Palma (, ), also known as ''La isla bonita'' () and historically San Miguel de La Palma, is the most northwesterly island of the Canary Islands, a Spanish autonomous community and archipelago in Macaronesia in the North Atlantic Ocean. La Pa ...

in the Canaries.

WASP-17b WASP-17b, officially named Ditsö̀, is an exoplanet in the constellation Scorpius that is orbiting the star WASP-17. Its discovery was announced on 11 August 2009. It is the first planet discovered to have a retrograde orbit, meaning it orbits ...

, the first

exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first det ...

known to have a

retrograde orbit Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is, the central object (right figure). It may also describe other motions such as precession or ...

was discovered in 2009 using this array.

KELT-South

KELT-South (''Kilodegree Extremely Little Telescope South'') is a small robotic telescope that is designed to detect transiting extrasolar planets. The telescope is owned and operated by

Vanderbilt University Vanderbilt University (informally Vandy or VU) is a private university, private research university in Nashville, Tennessee, United States. Founded in 1873, it was named in honor of shipping and railroad magnate Cornelius Vanderbilt, who provide ...

and was based on the design of KELT-North, which was conceived and designed at the

Ohio State University The Ohio State University (Ohio State or OSU) is a public university, public Land-grant university, land-grant research university in Columbus, Ohio, United States. A member of the University System of Ohio, it was founded in 1870. It is one ...

, Department of Astronomy. The KELT-South telescope will serve as a counterpart to its northern twin, surveying the southern sky for transiting planets over the next few years.

MeerLICHT

:''Observatory Code: '' Optical wide-field telescope, installed in 2017. It has a effective aperture, and a 1.65 x 1.65 degree field-of-view, sampled at 0.56"/pix. It was designed and manufactured in the Netherlands (

Radboud University Radboud University (abbreviated as RU, , formerly ) is a public research university located in Nijmegen, Netherlands. RU has seven faculties and more than 24,000 students. Established in 1923, Radboud University has consistently been included in ...

& NOVA) and is run by a consortium of Radboud University, University of Cape Town, the NRF/SAAO, the University of Oxford, the University of Manchester and the University of Amsterdam. It is the optical eye of MeerKAT, and has as its main-purpose to twin with the MeerKAT radio array to achieve a simultaneous optical-radio coverage of the Southern Skies. It is the prototype of th
BlackGEM
array, installed at ESO La Silla in Chile. MeerLICHT Fisheye

Yonsei Survey Telescopes for Astronomical Research (YSTAR)

:''Observatory Code: '' The Yonsei Survey Telescopes for Astronomical Research (YSTAR), decommissioned in 2012, was used for the monitoring of variable stars and other transient events. YSTAR was a joint project between SAAO and the

Yonsei University Yonsei University () is a Private university, private Christian university, Christian research university located in Seoul, South Korea. Yonsei is one of the three most prestigious universities in the country, part of a group referred to as SK ...

Korea Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically Division of Korea, divided at or near the 38th parallel north, 3 ...

Asteroid Terrestrial-impact Last Alert System (ATLAS)

The ATLAS asteroid impact early warning system, developed by the University of Hawaii and funded by NASA, consists of 4 telescopes; South Africa hosts ATLAS-Sutherland. In February 2023, the telescope observed the comet C/2023 A3 (Tsuchinshan–ATLAS).

Geophysical

South African Geodynamic Observatory Sutherland (SAGOS)

The GeoForschungsZentrum, Potsdam in co-operation with the

constructed the SAGOS between 1998 and 2000. SAGOS consist of a 1 Hz permanent GPS station, a superconducting gravimeter, meteorological sensors, and a tri-axial magnetometer. The GPS station is also used in support of the CHAllenging Minisatellite Payload (''CHAMP'') and

Gravity Recovery and Climate Experiment The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of it ...

(''GRACE'') space missions.

SUR Station

The SUR station forms part of the International Deployment of Accelerometers Project and the

Global Seismographic Network IRIS (Incorporated Research Institutions for Seismology) was a university research consortium dedicated to exploring the Earth's interior through the collection and distribution of seismographic data. It operated the U.S. National Science Foundati ...

of the

Incorporated Research Institutions for Seismology IRIS (Incorporated Research Institutions for Seismology) was a university research consortium dedicated to exploring the Earth's interior through the collection and distribution of seismographic data. It operated the U.S. National Science Foundati ...